We’ve been all about bomber jackets these past few weeks so for our second installment of Back to School we chose to look back at the iconic piece of outerwear. As the name implies, the bomber jacket has blatant military roots but can now be found in the collections of some of the world’s most respected streetwear and high-fashion brands. Take a look below for the full story.

The bomber jacket, also known as the flight jacket, goes back nearly 100 years to the devastating but influential years of World War I. At the time, most aircraft weren’t equipped with enclosed cockpits causing the temperature to drop significantly while airborne, especially at higher altitudes. In order to stay warm in such conditions, pilots in Britain’s Royal Flying Corps wore long leather coats while serving in France and Belgium. The US army quickly caught on to their allies’ method and in 1917 established the Aviation Clothing Board. The board began manufacturing and distributing heavy-duty leather jackets which became the first American flight jacket – although it would be several decades until the jacket began to take the form we associate the term with today.

The board’s invention remained the jacket of choice up until World War II when professional parachutist Leslie Irvin put his design skills to use. Known for his daring adventurousness and athleticism, Irvin became the first person to free-fall parachute jump in 1919. Using his success and expertise, Irvin set up the Irving Air Chute Company which quickly became the largest parachute manufacturer in the world.

As technology allowed aircraft to fly faster and at higher altitudes, pilots required warmer outfits as ambient temperatures could drop to negative 58 degrees Fahrenheit at altitudes of 25,000 feet. In order to keep pilots warm in these conditions, the American stuntman designed and manufactured the classic RAF sheepskin flying jacket which quickly became standard issue for Britain’s Royal Air Force during most of World War II.

The United States, looking for their own version of Irvin’s popular design, introduced the A-2 jacket – a follow-up to the previous A-1 jacket adopted in 1927. After making sure the jacket met all necessary requirements, the U.S. Army Air Corps (later the U.S. Air Force) standardized the A-2 for military use on May 9, 1931. The jacket’s sturdy leather construction proved beneficial and even included some of the features associated with the modern bomber jacket like knitted wristlets and a waistband. The A-2 was also one of the first pieces of clothing designed expressly to use a zipper, a feature so ubiquitous now it’s hard to imagine otherwise.

The seminal jacket remained popular and became a symbol of wartime heroics as only certified Air Force officers and crewmen could obtain them. In spite of this, General H.H. “Hap” Arnold cancelled any further leather jackets in favor of cloth-shell jackets towards the end of the war since the immersion of jet aircrafts required a new type of apparel fit to the needs of higher altitudes and colder temperatures. A pattern seems to be emerging.

The B-15 became the jacket of choice after a few iterations and hinted at the design of jackets to come with its 2 front slash pockets, utility pocket on the left sleeve, and an overall lightweight feel. Although originally manufactured from cotton, the B-15 soon became one of the first flight jackets produced from nylon, a material discovered prior to World War II but not used for that purpose until afterwards. Besides an additional wool collar carried over from the earlier B-10, the B-15’s other features would later be used by the most recognizable and popular bomber jacket of all – the MA-1.

The MA-1 was initially designed by the Air Force and produced by Dobbs Industries (later Alpha Industries) under the specification MIL-J-8279 to serve as a mid-weight flight jacket for use year-round by using high-quality nylon on both the outer shell and lining. In just a few years, the inner would be replaced with polyester bringing the MA-1’s weight down even more while providing extra warmth. The latest version, favored by pilots in training, experienced its first combat use during the Korean War and was produced in a variety of colors. By 1960 however, the MA-1 was produced primarily in a Sage Green color and made reversible with a bright Indian Orange lining should the pilot crash and need an easily visible signal for rescue crew.

The jacket served its pilots well, but with the Vietnam War on the horizon the demand for MA-1s rose sharply leading to a dramatic increase in their production. Despite most Americans’ opposition to the televised war abroad, the MA-1 became a sought after garment and its main producer, Alpha Industries, began selling the jacket both commercially and to European Air Forces. The stylish jacket caught on with American youth and quickly became an inseparable part of pop culture thanks to people like Steve McQueen sporting the jacket onscreen.

The jacket’s popularity snowballed from there and within the next decade the versatile jacket had been adopted by various subcultures including the UK’s controversial Skinheads. The 1980s brought the jacket to a whole new generation of fashionistas once it was featured in influential style magazines like The Face and i-D. With the emergence of hip-hop, the genre’s forerunners exploited the jacket’s bagginess for a puffy silhouette favored among hip-hop heads at the time and largely to this day.

By the end of the new millennium’s first decade, however, a slimmer form-fitting silhouette began to overtake the loose, relaxed fit of years prior. Important designers took note and tweaked the iconic jacket’s specifications to their liking. Picturing the jacket as a near blank slate, unorthodox materials like wool and leather found their way into new designs while many formerly staple features were stripped away.

Take Saint Laurent’s latest bomber for instance. If it weren’t for the name, the jacket would have very little in common with the classic military jacket. Balenciaga went even further and took the jacket to the tropics with a trendy, colorful, all-over floral print.

Streetwear brands didn’t shy away from reinterpreting the jacket either like Supreme’s recently released (and promptly sold out) Crosses Bomber which acknowledges the MA-1’s heritage as a reversible garment.

With the benefit of hindsight, it seems the military’s most fashion-friendly design has reached a new height in recent years and shows no signs of slowing down. What was once designed solely for combatting the extreme temperatures faced at high altitudes is now an anticipated piece of almost every fashion house’s latest collection – at sea level no less. It almost doesn’t even make sense to refer to many of these pieces as a bomber jacket. But in the world of fashion, next to nothing makes sense and if we were all wearing clothing strictly for utilitarian purposes we’d be dressing like, well, the military, which might not be such a bad thing after all.